Apparatus and method for spraying terrain



July 31, 1956 O. J. GERBRACHT APPARATUS AND METHOD FOR SPRAYING TERRAINFiled sept. 14, 1953 2 Sheets-Sheet 1 July 31, 1956 o. J. GERBRACHTAPPARATUS AND METHOD RoR sPRAYTNG TERRAIN 2 Sheets-Sheet 2 Filed Sept.14, 1953 JIJ/Zilla? @xfa/1 J @man/1cm United States Patent O APPARATUSAND METHOD FR SPRAYHNG TERRAIN Osceola I. Gerbracht, Hettinger, N. Dali.

Application September 14, 1953, Serial No. 379,935 6 Claims. (Cl.299-43) This invention relates to an apparatus and method for sprayingterrain and, more particularly, to the controlled spray treatment ofplants growing thereon.

Numerous devices and methods have been proposed for spray treatingplants and weeds growing on the ground. There are two main problemswhich confront the user of such prior equipment. First, where it isdesired to vary the amount of spraying liquid to suit the type of plantsto be sprayed, no quick and easy method has been devised for accuratelychanging and controlling the amount of liquid delivered. Secondly, therate of speed at which the spraying vehicle travels over the groundcannot be held at a constant rate. Consequently, where a predeterminedrate of liquid ow is maintained, some portions of the ground willmaintain a heavier portion of spraying liquid than others. The problemis further intensified where it is attempted to control the rate of owthrough nozzles having pre-set characteristics. For example, if nozzlesor spray-heads are designed to deliver a certain quantity of liquid perhour, such quantity should be maintained in order to properly apply thesprayed liquid. The -size and direction of the orifices in thespray-heads, the distance separating the spray-heads and the distancefrom the spray-heads to the ground are all more-or-less fixed withrelation to the spraying characteristicsjof the nozzles. If the rate offlow of liquid is cut down to a fraction of the ideal rate, the amountof ground area covered will be lessened and the concentration of liquidinvariably becomes uneven. Thus, where weeds are being treated toselectively kill them while maintaining the healthy growth of desirableplants, such weeds may not receive a suicient concentration to beeffective. On the other hand, those areas receiving too great aconcentration will cause not only the weeds to be killed, but also thedesirable plants.

It is, therefore, a general object of this invention to overcome theabove noted diiculties and to provide an apparatus and method forefficiently and conveniently spraying terrain under conditions which are"controllable over a wide range of circumstances.

It is another object of the invention to provide a. method and apparatusfor delivering a variable but predetermined quantity of active chemicalto the terrain and plants growing thereon which will be proportionate tothe rate of travel over the ground, all the while preserving the idealspray characteristics of the nozzle assembly.

It is a further object of the invention to provide an apparatus fordelivering a characteristic rate of liquid under con-stant pressurethrough pre-set spray-heads, yet varying and controlling the activity ofthe liquid with respect to its treating power on the terrain and plantsgrowing thereon.

It is a still further object of this invention to provide inexpensiveand simple treatment for fertilizing, killing insects, killing weeds andthe like which will maintain a high degree of sensitivity and controlwith a minimum of attention on the part of the operator.

These and other objects and advantages will morevfully 'ice appear fromthe following description made in connection with the accompanyingdrawings wherein like reference characters refer to the same or similarviews and in which:

Fig. l is a plan view of my spraying vehicle in attached position to apower vehicle such as a tractor, the forward portion of the tractor andportions of the spray vehicle being superfluous and cut away;

Fig. 2 is a side elevational View of my spray vehicle;

Fig. 3 is a diagrammatic representation of the spraying reservoirs andmechanism; and

Fig. 4 is an enlarged detailed View of the chemical pumping means,portions thereof being shown in vertical section on a line 4-4 of Fig.l.

Referring now more particularly to the drawings, my device constitutes aspray vehicle which is preferably in the form of a wheeled vehicle 10 asshown in Fig. l. The wheeled vehicle has a framework 11 to which may bejournalled wheels 12 and 13, as shown. A drawbar 14 is rigidly securedto framework 11 and extends forwardly to terminate in a clevis 15 whichis adapted to be secured as at pin means 16 to the rear end of a tractoror other vehicle 17, as shown. The wheeled vehicle 10 may be providedwith other structures such as braces 18 and has secured Vat the rear endthereof a spray assembly indicated generally at 19.

The spray assembly constitutes spray arm-s 2t) in the medial rear areaof the wheeled vehicle and preferably has, in extensible relationtherewith, a pair of side arms 21 and 22. The spray arms 20, 21 and 22are tubular .in nature and constitute a manifold having nozzles orlspray-heads 23 secured in liquid communication with the manifold inspaced relation, as shown. The spray-heads are preferably of ordinaryconstruction and are adapted for fixed optimum spraying conditions undera constant pressure head. The space between the nozzles o-r sprayheads23 is so constructed as to bring the sprayed areas in abutting relationwith very little overlapping. The extendible arms 21 and 22 are hingedat vertical pivot points 24 and 25 respectively and the arms 21 and 22are respectively connected to the medial arm 20 for liuid communicationby liexible couplings 26 and 27 respectively. The arms 21 and 22 canthus be pivotally swung to the rear so as to be out of the way when thewheeled vehicle i0 is transported, for example, along a highway. When inextended position, as shown in Fig. l, the spray assembly overlies theterrain in spaced clearance and is parallel therewith and transverse tothe direction of travel which is longitudinally of the drawbar 14.

Two independent pumping systems are mounted upon the wheeled vehicle 10,one for circulating and delivering carrying fluid such as water and theother for circulating and introducing an active chemical into thespraying assembly.

The carrying Huid system has a reservoir or tank 23 mounted on theframework 11, preferably in a lateral position, as shown in Figs. 1 and2. The reservoir or tank 28 is adapted to hold a carrying fluid such aswater and has a capped opening 29 bearing a supply line such as suctiontube 30 having an extension communicating with the 'internal portion ofthe tank (not shown). The suction tube 30, in turn, extends forwardly toa pumping mechanism 31 which may be driven by a source such as the powertake-off of the tractor 17. The outlet of the pump 31 communicates withanother portion of the supply line such as the pressure tube 32 which inturn terminates in a strainer member 33. The strainer member 33communicates, in turn, with a regulating valve 34, and a pressure gauge35 communicates with the pressure tube 32, the strainer member 33.Further forming a part of the carrying fluid supply line is the tube 36for delivering carrying uid under a preselected constant pressure fromthe regulating valve 34. A shut-off valve 37 may be interposed betweenthe tube 36 and the regulating valve 34 for completely shutting off theline when so desired. The tube 36 communicates with the injecting andmixing portion of the system which, in turn, communi- Cates with thespray assembly i9 and which will be described subsequently in thisspecification. The regulating valve 34 has an overflow or by-pass tube38 which leads back to a capped opening 39 communicating in turn withthe internal part of tank 28. Thus, when the flow of carrying fluidthrough the supply system would tend to cause a pressure increase in thetube 36 over and above that controlled by regulator 34, then theadditional surplus carrying fluid will be returned to by-pass 38.

it will be noted that the carrying fluid system described thus far willconstitute an independent source of fluid under constant pressure whichwould be delivered at the optimum spraying pressure for the nozzles ofthe spray assembly. In other words, with the regulator valve 34 properlyadjusted, the system thus far described will deliver a uniform andproper spray over the entire area to be traversed during the travel ofthe wheeled vehicle 10.

The other fluid system comprising an essential part of my invention isthe active chemical system which injects the proper amount of treatingsubstance into the spraying liquid under carefully controlledconditions. The chemical system has a tank or reservoir 44E also mountedupon the framework 11 and preferably on a rack 41 securely lixedthereto, as shown in Figs. l and 2. Since the proportion of chemical tocarrying uid is quite low, the tank or reservoir 40 need only be afraction of the size of the tank 2.8. The small tank 40 has a suctiontube 42 communicating with the internal contents thereof, the tube 42extending downwardly as shown in Fig. 2 and communicating with a pumpmechanism indicated generally at 43 as shown in detail in Fig. 4. Thepump 43 has a cylindrical barrel 44 which is mounted in fixed relationto the bearing structure 45 of the framework 1l, the mounting beingaccomplished through such means as bracket 46 secured to bearing mount45 as by bolts 47. The upper portion of barrel 44 is screwthreaded to avalve element 48 having a liquid tight connection 49 with the chemicalsupply line or tube 42. interposed between the internal space of thebarrel or cylinder 44 and the supply line 42 is a check valve 5! whichis preferably in the form of a spring-pressed ball seated on a taperedbearing area 51. The ball check valve S0 will permit the flow ofchemical through line 42. and into the internal space of the cylinder orbarrel 44 but will not permit the return of iiuid through the line. Alsocommunicating with the cylinder of barrel 44 is an outlet passageway 52which leads through connector 53 into the pressure side of the chemicalsupply line 54. A similar check valve 55 lies in the outlet passageway52 and is seated against a tapered bearing area 56. The spring-pressedball check valve 55 will permit the exit of fluid chemical through theoutlet 52 and into the supply line 54 but will prevent the return of thechemical into either the valve 43 or the supply line 42. The delivery oroutlet tube S4 of the chemical supply line also communicates with thespray assembly 19 as will be described.

The plunger portion of the pump 43 constitutes a piston 57 which may besupplied with a recessed annular groove 58 for bearing a liquid sealingmeans such as an O-ring 59. Longitudinally of the piston 57 is astraight bore 60 which slidably receives an actuating piston rod 6l asshown in Fig. 4. The lower portion of piston 57 bears a shoulderedextension 62. which retains a compression spring 63 bearing in turnagainst a lower shoulder 64 formed on the lower peripheral edge ofcylinder or barrel 44. The compression spring 63 continually urges thepiston 57 downwardly against the abutting action of piston rod 6l withinthe bore 60. The outward end of the piston rod 6l terminates in athreaded end 65 which bears a pair of nuts 66 and 6'7 in spacedrelation. Slidably receiving the portion of the piston rod 61 lyingbetween the nuts 66 and 67 is a sleeve 68, as shown in Fig. 4. A washer69 may be positioned against nut 66 and an overload compression sprng 76interposed between the washer 69 and a shoulder portion '7l of thesleeve 68. The sleeve 68 has journalled at its outermost end a camfollower '72, as shown. A radius arm 73 is piv'oted to the mountingstructure 45 by pivot pin 74 and is pivoted at the other end to theshaft 75 which is co-axial with the cam follower 72. Cam follower 72rides continuously upon a four-lobe cam 76 which, in turn, is mountedupon the wheel shaft '77 of the wheel i3, in turn journalled toframework ll, as shown in Fig. l. Compression spring 70 permits thesleeve 68 to oscillate suiciently to take up any misalignment incurredthrough. the action of radius arm 73 during the turning movement of cam76.

Means for adjusting the length of stroke of the piston 43 andconsequently limiting the delivery quantity of chemical for each strokeof the pump is shown generally at 78. The adjusting means comprises apivotally mounted stop arm 79 having its point of pivotal attachment Si?secured to an ear 8l formed on the mounting structure 45. The other endof the stop arm 79 has a connection 2 to a control rod 83 which may, inturn, be housed within a flexible cable 84 mounted at S5 to the mountingbracket 46 as shown. The upper surface 86 of stop arm 79 is adapted toengage the shouldered portion 62 of the piston 57 as will be describedunder the operation of the device. Adjusting rod S3 communicates at itsupper end with a manually operable lever S7 which will extend or retractthe arm 79 in a preselected manner to adjust the radial position thereofwith respect to the pivotal point all. A dial or indicating gauge 88 maybe provided in connection with the manual adjusting handle 87 so as tovisibly indicate the positioning of stop arm 79 and to gauge thequantity delivery of liquid chemical. Braces or brackets 89 may beattached to framework 1l for support of the manual adjusting and gaugingmechanism as shown in Fig. 2.

Referring now to Figs. 1 and 3, the carrying fluid line 36 and thechemical line 54 both terminate in a mixing chamber 90 which is mountedupon and in communication with the spray assembly 19 as previously notedand as observed from Fig. 3. The upper end of the mixing chamber 90bears a cap 91 through which the chemical supply tube 54 communicates inliquid-tight relation. The carrying fluid line 36 is preferablyintroduced tangentially at 92 for creating a whirling mixing actionwithin the mixing chamber 90 as is common in the art. The product outletfrom the mixing chamber 9i) communicates through connecting tube 93,which in turn leads into the T-rnember 94. Each of the lateral openingsof the T-member 94 are secured in liquid communication with the arms ofthe spray assembly 19 which, in its diagrammatic form, does not show allof the spray-heads nor the complete hinged arm assembly.

In my method or procedure of spraying and in the use and operation of myapparatus, the reservoir 2S is lled with a carrying liuid, preferablywater, and the smaller reservoir 40 is supplied with suitable fluidchemical such as that employed in killing weeds preferentially in thepresence of useful plants. The pump 3l is energized so as tocontinuously pump water from tank 28 through the strainer 33 and intothe regulating valve 34. The water pressure supplied through the line 36may be adjustably fixed so that it will be delivered at a continuous anduniform rate through spray-heads 23, as previously pointed out, theoverflow or excess water being recirculated through the by-pass line 38back to reservoir 28,

When the power vehicle 17 is set in forward motion, the cam element 76will turn with wheel shaft 77 in response to the rotation of wheel 13over the ground. With the particular cam shown, the four lobes willcause -ratus. `purposes may require adjustments whereby greater or fourreciprocations of piston 57 for every turn of the Wheel 13. At eachreciprocation or stroke, the piston 57 will suck in a quantity ofchemical through line 42 and past the check valve S1. The suction ordownward stroke of the piston 57 is accomplished through the action ofcompression spring 63. When, however, the shoulder portion 62 of thepiston 57 abuts against the upper surface 86 of stop arm 79, thedownward travel of the piston 57 will be stopped. The piston rod 61,however, will continue downwardly as the cam follower 72 rides on thelobes of cam 76. As the cam follower 72 begins to climb upon the nextcam lobe, the piston rod 61 will reciprocate in the opposite directionand again abut against the upper end of opening 60 in the piston 57. Thepiston 57 will then begin its upward travel, forcing iluid chemical fromthe piston chamber through the outlety 52 and into the chemical supplyline 54 from which it enters the mixing chamber 90 and becomesintimately injected and intermixed with the water from the supply line36. It will be noted that the quantity of chemical liuid will beconstant for any given number of rotations of the wheel 13 at any givensetting of the stop arm 79. Thus a lixed and controlled quantity ofchemical will be delivered per unit area of terrain traveled over by thewheeled vehicle regardless of the speed at which the vehicle travels.This is in contradistinction to the rate of supply of carrying iluidwhich remains constant rega-rdless of whether the wheeled vehicle istravelling at a high or low rate of speed or is travelling at all, forthat matter. The quantity of carrying fluid or water supplied to thespray assembly is such as will give an optimum spray over the width ofthe assembly. This quantity should not be such as will drip or run olplants sprayed in the normal course of events. I have found that a goodaverage rate of application of water to the spray assembly is six orseven gallons per acre traversed. I may achieve good results with as lowa quantity as ve gallons per acre and as high as ten gallons per acrewith the particular equipment built. With respect to the chemical whereordinary weed killing liquids are employed, I may inject, for example,from one-third to one-half a pint per acre of terrain. Since plants suchas ax and corn have a tolerance range which will not withstandquantities of certain weed killing7 chemicals in excess of one-half apint per acre, more than that quantity will kill the corn or flax whileless than one-third of a pint per acre will not be effective in killingweeds. The above specific additions apply only to one type of fluid`chemical which may be usefully employed in my appa- Chemicals ofdifferent types and for different lesser quantities of chemical per acrebe delivered. In any event, the remarkable sensitivity and control of myequipment makes possible the safe and sure application of these potentchemicals while, at the same time, obtaining maximum effectiveness fromthe treatment.

In adjusting the stop arm 79, the backward stroke of piston 57 can beincreased by lowering the arm from its position shown in Fig. 4. On theupward stroke, the quantity of chemical in the chamber delivered throughthe outlet 52 will thus be increased. It will be noted that the newsetting of stop arm 79 will effect a delivery of new quantity ofchemical per acre sprayed regardless of the speed of forward travel. Theentire injection of chemical is thus automatically compensated formerely by selecting the indicated quantity of chemical which it isdesired to spray per acre of terrain. yThe amount of chemical injectedinto the mixing chamber 90 is such as will not substantially aifect thespraying characteristics of the spray assembly. Thus, for example, whereseven gallons of water per acre is the amount of carrying liuiddelivered through the spray-heads, adding a differential of severalpints per acre to the quantity of carrying fluid will not 'materiallyalter the pattern of spray or the uniformity of application.

It may be further mentioned that, because my mixing chamber is, in closeassociation with the spray assembly, `I can effect almost instantaneouschanges in concentration within the mixed liquid which is sprayed fromthe nozzles. The latter is important when patches of weeds areencountered which may be of a different and hardier variety than thegeneral -run within the area to be sprayed. Thus, with the relation ofthe concentration required to kill a patch of difficult weeds, I canchange the concentration at that particular point and again lower theconcentration when the dicult area has been passed.

My method of spraying can be usefully employed in the art of sprayingplants to kill blight and bugs or may even be employed to disseminateliquid fertilizer to the ground itself. In all events, my control overthe concentration of sprayed lluid is of extremely high quality whichmakes for eiiicient results at lower operating cost.

It will, of course, be understood that various changes may be made inthe form, detail, arrangement and proportion of the parts Withoutdeparting from the scope of my invention which consists of the matterdisclosed herein and set forth in the appended claims.

What is claimed is:

1. A machine for travelling over the terrain and spraying plants growingthereon comprising, a supply line for delivering carrying fluid, spacednozzles for overlying the terrain during operation of the machine, meansfor supplying carrying iluid under substantially constant pressure fromsaid supply line to said nozzles to deliver the carrying fluid at asubstantially continuous and controlled manner through said nozzles, asupply line for providing a quantity of active chemical, a pump forinjecting relatively small controlled quantities of chemical from saidchemical supply line to the carrying fluid supply line, and means forpreselecting a relatively small quantity of chemical to be injected fora given area of terrain, said pump being automatically compensated forthe rate of travel of said machine so as to maintain the amount ofchemical delivered to said given area at a substantially constant value.

2. A machine for travelling over the terrain and spraying plants growingthereon comprising, a wheeled vehicle, a reservoir for water, a sprayassembly in spaced clearance with the terrain, means for supplying waterunder substantially constant pressure from said reservoir to the sprayassembly to deliver water at a substantially continuous and controlledmanner through the spray assembly, a reservoir for active chemicalliquid mounted on said vehicle, means responsive to the travel of saidmachine over the terrain to deliver a relatively small amount ofchemical proportionate to the rate of travel into a portion of saidwater supply, and means for maintaining a constant and even flow ofliquid through said spray assembly whereby to maintain a substantiallyeven and constant rate of flow of the total liquid, yet controlling thequantity of active chemical liquid per unit area of terrain.'

3. A method of chemically treating large areas of terrain which consistsin pressurizing water to a constant predetermined value, delivering saidpressurized water to a spray assembly and causing it to be sprayeduniformly therethrough while moving said spray assembly over the terrainin a prescribed path, simultaneously injecting and mixing with saidwater in proportion to the rate of travel over the terrain a continuousquantity of chemical for spraying therewith, said quantity of chemicalbeing of such low ratio with respect to the quantity of water as willnot materially affect the uniformity of spray.

4. A method of chemically treating large areas of terrain which consistsin sprayingV uniformly a substantial quantity of water at a fixed ratethrough a spray assembly, independently moving said spray assembly overthe terrain in a prescribed pat-h, simultaneously injecting and mixingproportionately to the rate of movement over the terrain a quantity offluid chemical into said water for spraying therewith, adjustablycontrolling the quantity 7 of fluid chemical for any given rate oftravel without disturbing said proportionate injecting and mixing, saidquantity of chemical being of such low ratio with respect to thequantity of carrying Huid as will not materially affect the uniformityof spray.

5. A machine for traveling over the terrain and spraying plants growingthereon comprising, a supply line for delivering carrying fluid, aplurality of nozzles having fixed oriiice structure and iixed relativepositions during operation of the machine in its travel over theterrain, said plurality of nozzles each having iluid connection withsaid supply line, ymeans interposed in said supply line maintaining saidcarrying iiuid under substantially constant pressure to deliver thecarrying iluid to the terrain at a substantially continuous andcontrolled manner through said nozzles, a chemical supply line in fluidconnection with said carrying iluid supply line, and a pump interposedin said chemical supply line driven by and at a rate proportionate tothe rate of travel of the machine for injecting relatively smallcontrolled quantities of said chemical from the chemical supply lineinto the carrying fluid.

6. A method of chemically treating with spray nozzle equipment largeareas of terrain which consists in uniformly spraying under constantpressure a substantially Xed quantity of carrying fluid per unit oftime, independently moving the nozzle equipment over the terrain in aprescribed path, and simultaneously injecting and mixing chemical intosaid carrying uid at a iixed quantity per unit of'terrain area and inlow quantity ratio so as to preserve substantially the uniformity ofspray irrespective of the rate of injection of the chemical.

References Cited in the le of this patent UNTTED STATES PATENTS

